Internal-combustion engine.



No. 696,547. Patented Apr. L. |902.

P. BURT.

INTERNAL COMBUSTIGN ENGINI;

(Application lad Aug. 19. 1901.)

(NoModel.)

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i i j/C ry m fa 6 n' 1 *I l z 1'/ |r fb S 7 WITNESSES :d INVENTORAlz'orney :Unteren @trarne Fahrtzeit @unica PETER BUI-t1, OFI'IOILYBANK, BOTIHVELL, SCOTLAND.

NTERNAL=CQMBUSTION ENGBNIE.

SPECIFICATION forming part of Letters Patent No. 696,547, dated .April1, 1902.. Application tiled August 19, 1901. Serial No. '72,525 (Nomodel.)

To @ZZ 1071/0711/ it may concern:

Be it known that I, PETER BURT, a citizen of the United Kingdom of GreatBritain and Ireland, residing at Hollybanlr, Bothwell, Scotland, haveinvented certain new and useful Improvementsin and Relating to Internal-Combustion Engines, (for which application for patent has been made inGreat Britain, No. 23,696, dated December 28, 1901,) of which thefollowing is a specification.

This invention has reference to internalcombustion engines of the classhaving their cylinders arranged in tandem fashion and havingsingle-acting pistons working in the Beau de Rochas or ordinaryfour-step cycle and transmitting their impulses both in the samedirection.

My improvements consist (as shall be hereinafter described in such amanner as to be readily understood by those having a knowledge of theart to which it relates) in constructing engines of this class so thatadvantage may be taken of the principle of compounding for the purposeof expanding the charges beyond their original voluine,.as Well as toprovide means whereby a current of cool air may be sent through thecompressionspace of each cylinder at the end of its exhaust-stroke forthe purpose of displacing the products of combustion from and coolingsaid compression-space.

In the drawings, Figure l is a vertical section through the cylinders.Fig. 2 is a crosssection taken on the line a; @c in Fig. 1.

These drawings illustrate an internal-combustion engine constructed inaccordance with my invention. The engine therein illustrated is avertical tandem engine, having all its cylinder' above, and its pistonsacting upon one crank, each of the high-pressure pistons receiving animpulse each cycle.

As shown by the drawings, in carrying out my invention I place betweenthe high-pressure cylinders c and b and in the same line therewith aproportionately larger cylinder c, hereinafter termed the low-pressurecylinder,7 the respective pistons d, e, and f of these cylinders beingconnected together by a piston-rod g and the lower piston e acting bymeans ot' its connecting-rod 7L upon the engine-crank. The exhaust-portst j of the highpressure cylinders a and l), respectively, arc

connected together (outside of the exhaustvalves i', which are balanced)by means of a pipe 7s, the port j being connected with the bottom end ofthe low-pressure cylinder by means of a passage Z. At the end of eachimpulse-stroke in the high-pressure cylinders these cylinders exhaustalternately into the low pressure cylinder, which latter being larger inarea (as its piston moves to the end of its upward stroke) expands thehot gases to a still greater volume, the piston nally uncovering aseries of exhaust-ports m in the cylinder c, whence these gases are freeto make their escape to the atmosphere. The air-inlet ports n and o ofthe high-pressure cylinder a and l), respectively, and the upper end ofthe low-pressure cylinder c are connected together (outside theair-valves n of the former) by means of a pipe p, this pipe being fittedwith an automatic non-return valve q. The low-pressurepiston fon itsdownstrolze draws in a charge of air by way of the valve q, which chargeof air being compressed on the return stroke of the lpiston f rushes(when either of the air-valves s of the high-pressure cylinders a l2 areopened) through the compression-space and escapes by the ports in thelow-pressure cylinder c, sweeping before it the products of combustionand at the same time cooling those chambers and valves.

If desired, air can be admitted behind the valve n through a valve q',as shown in Fig. 2, said valve q having the same function as the valveq, (shown in Fig. 1;) but it is not necessary to have any valve, such asvalve q', behind the valve W.

The piston-rods and pistons are made hollow, so that these may be keptcool by means of air or water, the air or water being admitted by a piper from any air or water supply.

`The pipe r extends downward through the hollow piston-rods s and g tonear the closed bottom of the latter and is provided with an openlowerend, from which the water or air passes and enters the hollow piston cby oriices in the piston-rod, the water or air circulating upward by wayof thc annular space between the pipe fr and the piston-rod g to theinterior of the piston f and d, whence it finally escapes by way of theannular space in the piston-rod What I claim is- 1. In aninternal-combustion engine, the combination, with a 10W-pressurecylinder, of two high-pressure cylinders of smaller diameter than thelow-pressure cylinder and arranged axially in line with it and atopposite ends thereof, an exhaust-pipe connecting the working ends ofthe high-pressure cylinders, and a passage connecting the saidexhaustpipe with the Working end of the said lowpressure cylinder,substantially as set forth.

2. In an internal-combustion engine, the combination, with alow-pressure cylinder, of two high-pressure cylinders of smallerdialneter than the low-pressure cylinder and arranged axially in linewith it and at opposite PETER BURT.

Witnesses:

JEssIn CAMPBELL, ROBERT BROWN.

